Screw.



the city and county .the divergent .slot or channel mad-e transverselyacross it turn the screw a safe and powerful means.

TINITED VSTAZIES P grE 'r' OFFICE.

' SCREW.

Specification of Letters Patent.

Patented March 12, 1907.

Applicatioii filed September 17, 1966. Serial No. 384,945.

To all whom it may concern: Be it known that I, JAMES H. CLAIBORNE, Jr.,a citizen of the United States, residing ,at of San Francisco and Stateof California, have invented new and useful Improvements in Scfews, ofwhich the following is a specification.

My invention relates to im wood-screws, and is particu to provide ascrew-head with means which out injuring orbrea Iticons'ists in the ofthe screw .with s terior socket, to which vice may be applied.

Referring to the accompanying drawing for-a more complete explanation ofmy invention, Figure 1 is a view ofthe screw, showing the head andsocket. Fig. 2 is. a

rovements in arly. designed y the screw can be readily turned with- 'ngthe head.

formation of the head cially-constructed ina suitable turningdesectional view of the head and socket. Fig,

3 is a plan view of screw.

In the usual construction of wood-screws, comically-shaped. head has afor the recepltlion of the blade of a screwdriver, to w 'ch power may beapplied to in either direction. Such screws when used in hard wood orwhen oxidized are difficult to turn, and when suflicient pressure .isbrought upon the screw-driver the head is either partially cracked offor the slot in the head will be'so marred and broken by the action ofthe screw-driver that it will be impossible to turn the screw.

It is the object of my invention to provide screw can be turned withoutdanger of breakage.

' A- 's a wood screw shank having the divergent conically-shaped head2,. this head hemg either fiat, convex, desired shape on the top. Withinthis head and interior to the peri hery I form a sunken chamber 3, whichis of greater length side walls of which intersect.

by which the or other suitable or- 1 in one direction than the othertransversely. This chamber has its walls substantially parallel with theaxis of the screw; As hereshown' it consists of two cylindrical openingsinter-- secting'each' other so as to leave inwardlyprojecting points atthe intersection, as shown at 4. A screw-driver having the pointsimilarly formed is adapted to fit this double chamber, and it will bemanifest that any required power within the strength-of the parts may beapplied to turning the a screw without danger of breaking or marrlng thehead, since the screw-driver will form-a lock with the openings ofthe'screw-head, and it will also serve to hold the screw in positionwhen the screw is to be started into the Wood.

Having thus described my invention, what I claim, and desire to secureby LettersPat ent, is

1. In awood-screw the head thereof rovided with a single sunken chamberw ose walls are-substantially parallel with the axis of thescrew saidchamber being in the form of two substantially cylindrical portions the2. Awood-screw having a head with a sunken chamber whose length isgreater than its width, said chamber consisting of two cylindricalportions whose walls are parallel with the was of the screw and whoseadjacent sides intersect to form a single connecting-chamber havinginwardly-projecting points at opposite sides of the centralportionthereo Y In testimony whereof I have hereunto set my hand inpresence of two subscribingwitnesses.

JAMES H. CLAIBORNE, JR. Witnesses z I I JAMES Mason, Q. P. S'rmonn.

